Full swing · Changes the swing

Towel under the arms

Setup in 3D
3D view
Setup from above
From above

Tuck a towel under both armpits and keep it there through half swings. The towel staying in place is the whole task.

Trains
Slice, Swing path
Dose (suggestion)
15 balls
Count
Swings where the towel stays until after impact, out of N
Stop signal
Stop: pain 3 out of 10 or more, pain spreading into an arm or leg, numbness, or more pain the next morning.
Source
Ten to Scratch: Cure your slice